What does my camera's white balance setting do?

[caspill]

What does my camera's white balance do?
What is color temp on the 5d, what does adjusting that do?

[Colin Southern]

what is color temp on the 5d, what does adjusting that do?

It adjusts the image to compensate for the fact the the colour (or colour temperature) of the sun's light changes throughout the day (also artificial lights often have vastly different colour temperatures). If the colour temperature set on the camera doesn't match the colour temperature of the lighting you're shooting in then you're likely to end up with people having orange or blue skin etc. Best to leave it set to Auto until you get the hang of it.

[caspill]

so its something to do after the fact? or before you snap the shot

[Dave Humphries]

Hi caspill,

If you set the camera to Auto (White Balance), most of the time you won't need to do anything afterwards.
If you shoot RAW, rather than jpg, you can do it (again) afterwards just as easily.

In fact there is a fairly hot thread on that very question; Color Balance: During the shoot vs RAW post-processing

However, shooting RAW would require some effort with a computer to process the pics before you could use them, or pass them on to anyone (which you may not have time for if touring), so you may want to stick at shooting with jpg, at least for now.

Cheers (and welcome),

[caspill]

what does the white balance actually do though? sorry for all the question, but im a complete novice.

[Colin Southern]

what does the white balance actually do though? sorry for all the question, but im a complete novice.

In summary it changes the way the camera processes colour information. Easiest way to see what it does is to take a series of shots with the white balance set to each possible setting, and see the difference you get in the results.

[Dave Humphries]

In a sentence; It makes a photo of a white sheet of paper look white in the picture.

If you have a fixed white balance set to "Daylight/Sunny", and take a picture of a white sheet of paper in these four places;
1) Outside, in the sunshine on a sunny day
2) Outside on a cloudy day
3) Indoors with filament (bulb) lighting
4) Indoors with flourescent (tube) lighting
Only in 1) above would the sheet appear white.
In 2) it would look blue, in 3) it would look yellow and in 4) it may even look slightly green

This is because of the colour temperature that Colin was explaining about.

Now we know that the piece of paper didn't really change colour, it was the light that was different.
The camera's white balance controls are what can make the white paper look white in all 4 places, either by manually doing it, or, as suggested, by setting it to "Auto"(matic).

Beyond my ramblings here, I would recommend you read Sean's Tutorial on the topic. It has demo pictures that will show what we mean. It goes into more detail than you need in places, but skim thorugh and try the mouseover on some of the pictures.

Cheers,

[caspill]

thanks a lot!

[dendrophile]

Caspill,

Not the best source image in the world, but here is a shot I took in RAW. Once on the computer I have adjusted the colour temperature to the values shown, and then sliced the different versions together. Note how the lefthand side looks cold (blue) and the righthand side looks warmer (red). That's the effect of changing the white balance. Here I have changed the colour temperature, effectively saying what colour white light is.

In Dave's description earlier, his (1) through (4) are presets that the camera has, knowing what white light is like in cloudy conditions, for example.



HTH,
Graham